U.S. patent application number 14/067961 was filed with the patent office on 2015-01-01 for lens, led light source unit having the lens and led light source module incorporating the unit.
This patent application is currently assigned to HON HAI PRECISION INDUSTRY CO., LTD.. The applicant listed for this patent is HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to Po-Chou CHEN, Feng-Yuen DAI, Chau-Jin HU.
Application Number | 20150003063 14/067961 |
Document ID | / |
Family ID | 52115426 |
Filed Date | 2015-01-01 |
United States Patent
Application |
20150003063 |
Kind Code |
A1 |
HU; Chau-Jin ; et
al. |
January 1, 2015 |
LENS, LED LIGHT SOURCE UNIT HAVING THE LENS AND LED LIGHT SOURCE
MODULE INCORPORATING THE UNIT
Abstract
A lens includes a light incident face receiving light from an
LED light source, a light exit face, and a connecting face
interconnecting the light incident face and the light exit face.
The light exit face is a convex face. The connecting face includes
a plurality of inclined reflecting planes located at a
circumferential periphery of the lens and extending downwardly and
inwardly from a position near to an outer edge of the light exit
face toward the light incident face. The inclined reflecting planes
of the connecting face are positioned around an optical axis of the
lens. An LED light source module includes a plurality of the lens
each diverging light from a corresponding LED light source and a
light diffuser having a plurality of light diffusing units each
over a corresponding lens. Each light diffusing unit has a shape of
the regular hexagon.
Inventors: |
HU; Chau-Jin; (Tu-Cheng,
TW) ; DAI; Feng-Yuen; (Tu-Cheng, TW) ; CHEN;
Po-Chou; (Tu-Cheng, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HON HAI PRECISION INDUSTRY CO., LTD. |
New Taipei |
|
TW |
|
|
Assignee: |
HON HAI PRECISION INDUSTRY CO.,
LTD.
New Taipei
TW
|
Family ID: |
52115426 |
Appl. No.: |
14/067961 |
Filed: |
October 31, 2013 |
Current U.S.
Class: |
362/245 ;
362/296.01; 362/335 |
Current CPC
Class: |
G02B 19/0061 20130101;
F21Y 2115/10 20160801; G02F 1/133603 20130101; G02B 19/0028
20130101; F21V 5/04 20130101; G02B 3/00 20130101; G02F 2001/133607
20130101 |
Class at
Publication: |
362/245 ;
362/335; 362/296.01 |
International
Class: |
F21K 99/00 20060101
F21K099/00; F21V 13/04 20060101 F21V013/04; F21V 5/04 20060101
F21V005/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 28, 2013 |
TW |
102123089 |
Claims
1. A lens for diverging light from an LED (light emitting diode)
light source comprising: a light incident face configured for
receiving the light from the LED light source; a light exit face
opposite to the light incident face, and the light exit face being
a convex face; and a connecting face extending between the light
incident face and the light exit face; wherein the connecting face
comprises a plurality of inclined reflecting planes located at a
circumferential periphery of the lens and extending downwardly and
inwardly from a position near to an outer edge of the light exit
face toward the light incident face, and the inclined reflecting
planes of the connecting face are positioned around an optical axis
of the lens.
2. The lens of claim 1, further comprising an annular mounting face
interconnecting the connecting face and the light incident face,
wherein the light incident face is located at a center of the
mounting face and recessed inwardly from an inner edge of the
mounting face toward the light exit face of the lens.
3. The lens of claim 2, wherein each inclined reflecting plane of
the connecting face extends from a position near to the outer edge
of the light exit face toward an outer edge of the mounting
face.
4. The lens of claim 3, wherein the connecting face is radially
symmetrical relative to the optical axis of the lens.
5. The lens of claim 4, wherein the mounting face is a horizontal
plane, and an angle defined between each inclined reflecting plane
and the mounting face is equal to each other.
6. The lens of claim 5, wherein the angle defined between each
inclined reflecting plane and the mounting face is an obtuse angle,
and the obtuse angle is more than a sum of a right angle and a
critical angle for total internal reflection on the lens-air
interface.
7. The lens of claim 4, wherein the connecting face further
comprises a circumferential surface between the inclined reflecting
planes and the light exit face, and the circumferential surface
extends downwardly from the outer edge of the light exit face
toward the outer edge of the mounting face.
8. The lens of claim 7, wherein each inclined reflecting plane and
the circumferential surface intersect at an arc having a peak near
the light exit face.
9. The lens of claim 8, wherein a height of the circumferential
surface firstly decreases gradually and then increases gradually
from one endpoint toward another endpoint of the arc.
10. An LED light source unit comprising: an LED light source; and a
lens coupled to the LED light source; wherein the lens comprises a
light incident face, a light exit face opposite to the light
incident face and a connecting face extending between the light
incident face and the light exit face, and the light exit face is a
convex face; and wherein the connecting face comprises a plurality
of inclined reflecting planes located at a circumferential
periphery of the lens and extending downwardly and inwardly from a
position near to an outer edge of the light exit face toward the
light incident face, the inclined reflecting planes of the
connecting face are positioned around an optical axis of the lens,
and the LED light source faces the light incident face of the
lens.
11. The LED light source unit of claim 10, wherein the lens further
comprises an annular mounting face interconnecting the connecting
face and the light incident face, wherein the light incident face
is located at a center of the mounting face and recessed inwardly
from an inner edge of the mounting face toward the light exit face
of the lens.
12. The LED light source unit of claim 11, wherein each of the
inclined reflecting planes of the connecting face extends from a
position near to the outer edge of the light exit face toward an
outer edge of the mounting face.
13. The LED light source unit of claim 12, wherein the connecting
face of the lens is radially symmetrical relative to the optical
axis of the lens, and the mounting face is a horizontal plane and
has a shape of a regular hexagon, and an angle between each
inclined reflecting plane and the mounting face is equal to each
other.
14. The LED light source unit of claim 13, wherein the angle
defined between each inclined reflecting plane and the mounting
face of the lens is an obtuse angle, and the obtuse angle is no
less than a sum of a right angle and a critical angle for total
internal reflection on the lens-air interface.
15. The LED light source unit of claim 13, wherein the connecting
face of the lens further comprises a circumferential surface
between the inclined reflecting planes and the light exit face, and
the circumferential surface extends downwardly from the outer edge
of the light exit face toward the outer edge of the mounting
face.
16. An LED light source module comprising: a plurality of LED light
bars arranged side by side in an array, with each of the LED light
bar comprising a printed circuit board and a plurality of LED light
source units mounted thereon; and a light diffuser consisting a
plurality of light diffusing units each covering a corresponding
LED light source unit for diffusing light from the corresponding
LED light source unit; wherein each LED light source unit comprises
an LED light source and a lens coupled to the LED light source, the
lens comprising a light incident face, a convex light exit face
opposite to the light incident face and a connecting face extending
between the light incident face and the light exit face; wherein
the connecting face comprises a plurality of inclined reflecting
planes located at a circumferential periphery of the lens and
extending downwardly and inwardly from a position near to an outer
edge of the light exit face toward the light incident face, the
inclined reflecting planes of the connecting face are positioned
around an optical axis of the lens, and the LED light source faces
the light incident face of the lens; and wherein the LED light
source units of two adjacent LED light bars are arranged in a
stagger manner.
17. The LED light source module of claim 16, wherein the lens of
each LED light source unit further comprises an annular mounting
face interconnecting the connecting face and the light incident
face, and the light incident face is located at a center of the
mounting face and recessed inwardly from an inner edge of the
mounting face toward the light exit face of the lens.
18. The LED light source module of claim 17, wherein the connecting
face of the lens of each LED light source unit is radially
symmetrical relative to the optical axis of the lens, and the
mounting face is a horizontal plane and has a shape of a regular
polygon, an angle between each inclined reflecting plane and the
mounting face being equal to each other.
19. The light source module of claim 18, wherein the angle defined
between each inclined reflecting plane and the mounting face of the
lens is an obtuse angle, and the obtuse angle is on less than a sum
of a right angle and a critical angle for total internal reflection
on the lens-air interface.
20. The LED light source module of claim 18, wherein each light
diffusing unit has a shape of the regular polygon of the mounting
face of the lens.
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to a lens, a light
source unit having the lens and a light source module incorporating
the light source unit and a light diffuser, wherein the light
source unit and the light source module have an improved light
distribution pattern with a more uniform illumination.
DESCRIPTION OF RELATED ART
[0002] LEDs are solid state light emitting devices formed of
semiconductors, which are more stable and reliable than other
conventional light sources such as incandescent bulbs. Thus, LEDs
are being widely used in various fields such as numeral/character
displaying elements, signal lights, light sources for lighting and
display devices.
[0003] Nowadays, light emitting diode (LED) light sources are
widely applied for illumination, such as being used for backlight
module, indoor lighting or billboard illumination. An LED light
source unit includes an LED light source and a divergent lens
coupled to the LED light source to spread light. In use, the LED
light source units are arranged together on a mounting surface to
form an LED light source module in order to obtain a planar light
output.
[0004] However, a light intensity pattern of each LED light source
unit is circular such that an irradiation field region irradiated
from an LED light source unit partially overlaps adjacent
irradiation field region irradiated from adjacent LED light source
unit. In addition, a light intensity distribution of the LED light
source unit is mostly concentrated at an optical axis while becomes
gradually weaker towards a periphery thereof. Therefore, the LED
light module having the LED light source unit is difficult to
satisfy the requirements of uniform light distribution, unless a
great number of LED light source units are mounted on the mounting
surface. However, to do so will increase the cost, which is
unfavorable.
[0005] What is needed therefore is a lens, an LED light source unit
having the lens and an LED light source module incorporating the
LED light source unit and a light diffuser which can overcome the
above mentioned limitations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Many aspects of the present embodiments can be better
understood with reference to the following drawings. The components
in the drawings are not necessarily drawn to scale, the emphasis
instead being placed upon clearly illustrating the principles of
the present embodiments. Moreover, in the drawings, like reference
numerals designate corresponding parts throughout the views.
[0007] FIG. 1 is an isometric, perspective view of an LED (light
emitting diode) light source unit in accordance with an exemplary
embodiment of the present disclosure.
[0008] FIG. 2 is an inverted view of a lens of the LED light source
unit of FIG. 1.
[0009] FIG. 3 is a cross-sectional view of the LED light source
unit of FIG. 1, taken along a line III-III thereof.
[0010] FIG. 4 is a cross-sectional view of the LED light source
unit of FIG. 1, taken along a line IV-IV thereof.
[0011] FIG. 5 is a schematic view of an LED light source module
incorporating a plurality of LED light source units each is the
same as that shown in FIG. 1 and a light diffuser over the LED
light source units.
DETAILED DESCRIPTION
[0012] Referring to FIGS. 1, 2, 3 and 4, an LED (light emitting
diode) light source unit 1 in accordance with an exemplary
embodiment of the present disclosure includes an LED light source 3
and a lens 2 coupled to the LED light source 3. The lens 2 includes
a light incident face 201, a light exit face 21 opposite to the
light incident face 201, a connecting face 22 extending between the
light incident face 201 and the light exit face 21, and an annular
mounting face 20 interconnecting the light incident face 201 and
the connecting face 22. The LED light source 3 faces the light
incident face 201 of the lens 2.
[0013] The light incident face 201 is a concave face and radially
symmetrical relative to an optical axis X of the lens 2. The light
incident face 201 is located at a center of the mounting face 20
and recessed inwardly from an inner edge of the mounting face 20
toward the light exit face 21 of the lens 2. In the present
embodiment, the light incident face 201 is ellipsoid, and a major
axis of the light incident face 201 is collinear with the optical
axis X of the lens 2. Alternatively, the light incident face 201 is
paraboloid or spherical.
[0014] The light exit face 21 is a convex face and radially
symmetrical relative to the optical axis X of the lens 2. The light
exit face 21 defines a recess 211 in a center thereof, and the
recess 211 is recessed inwardly toward the light incident face 201
of the lens 2.
[0015] The connecting face 22 of the lens 2 includes a plurality of
inclined reflecting planes 222 located at a circumferential
periphery of the lens 2 and extending downwardly and inwardly from
a position near to an outer edge 212 of the light exit face 21
toward an outer edge 202 of the mounting face 20. The inclined
reflecting planes 222 of the connecting face 22 are positioned
around the optical axis X of the lens 2. In the present disclosure,
the connecting face 22 is radially symmetrical relative to the
optical axis X of the lens 2. More in details, the inclined
reflecting planes 222 of the connecting face 22 are radially
symmetrical relative to the optical axis X of the lens 2.
[0016] The connecting face 22 of the lens 2 includes a
circumferential surface 221 extending between the inclined
reflecting planes 222 and the light exit face 21. The
circumferential surface 221 extends downwardly from the outer edge
212 of the light exit face 21 toward the outer edge 202 of the
mounting face 20. Each inclined reflecting plane 222 and the
circumferential surface 221 intersect at an arc 2221 extending
upwardly from the outer edge 202 of the mounting face 20 to an apex
of the arc 2221 and then downwardly back to the outer edge 202. A
height of the circumferential surface 221 firstly decreases
gradually and then increases gradually from one endpoint toward
another endpoint of the arc 2221. There are six arcs 2221 connected
together end-to-end.
[0017] In the present embodiment, the inner edge of the mounting
face 20 is a circle, and the outer edge 202 is a regular hexagon
including six sides connected end-to-end. The inclined reflecting
planes 222 intersect with the mounting face 20 at six sides of the
hexagonal outer edge 202. The mounting face 20 is a horizontal
plane, and an angle 0 between each inclined reflecting plane 222
and the mounting face 20 is equal to each other. In the present
disclosure, the angle 0 is an obtuse angle which is no less than a
sum of a right angle and a critical angle for total internal
reflection on the lens-air interface. That is to say, the light
incident on the reflecting plane 222 is totally reflected by the
reflecting plane 222 toward the light exit face 21 of the lens
2.
[0018] The light incident face 201 and the mounting face 20
cooperatively define a receiving space 203. The LED light source 3
is received in the receiving space 203 and an optical axis of the
LED light source 3 coincides with the optical axis X of the lens 2.
The LED light source 3 may include an LED chip and an encapsulation
encapsulating the LED chip. The encapsulation may be made of
transparent silicone doped with fluorescent particles. By the
design of the lens 2, the light from the LED light source 3 can be
effectively diverged by the lens 2 into a large illumination
angle.
[0019] Referring to FIG. 5, an LED light source module 6 in
accordance with an exemplary embodiment of the present disclosure
includes a plurality of LED light bars 5 arranged side by side in
an array. Each LED light bar 5 includes a printed circuit board 4
and a plurality of LED light source units 1 mounted thereon. The
LED light source units 1 of two adjacent LED light bars 5 are
arranged in a staggered manner. The LED light source module 6
further includes a light diffuser 7 consisting a plurality of
regular hexagonal light diffusing units 71 each covering a
corresponding LED light source unit 1, whereby the light from the
LED light source units 1 can be more evenly mixed together before
the light emits from the LED light source module 6. Thus, the light
source module 6 can uniformly illuminate an object needing a planar
illumination, such as a liquid crystal display (LCD) or a sign
box.
[0020] In the present disclosure, light emitted from the LED light
source 3 is refracted into the lens 2 through the light incident
face 201, and a portion of light propagating toward the inclined
reflecting plane 222 is reflected toward the light exit face 21 by
the inclined reflecting plane 222, thereby creating an improved
light distribution pattern with a hexagonal irradiation field
having a large illumination angle.
[0021] In use, a plurality of LED light source units 1 are mounted
on the printed circuit board 4 to form the LED light bar 5, and a
plurality of LED light bars 5 are arranged side by side in an array
to form the LED light source module 6. Since the LED light source
units 1 of two adjacent LED light bars 5 are arranged in a
staggered manner, the LED light source module 6 creates a uniform
light output without bright spots.
[0022] It is believed that the present embodiments and their
advantages will be understood from the foregoing description, and
it will be apparent that various changes may be made thereto
without departing from the spirit and scope of the disclosure or
sacrificing all of its material advantages, the examples
hereinbefore described merely being preferred or exemplary
embodiments of the disclosure.
* * * * *